G31.84 Mild cognitive impairment of uncertain or unknown etiology
Billable ICD-10-CM code, FY2026.
Applicable to
Mild cognitive disorder NOS
Mild neurocognitive disorder of uncertain or unknown etiology
Excludes1 (never code together)
age related cognitive decline (R41.81)
altered mental status (R41.82)
cerebral degeneration (G31.9)
cerebrovascular diseases (I60-I69)
change in mental status (R41.82)
cognitive deficits following (sequelae of) cerebral hemorrhage or infarction (I69.01-, I69.11-, I69.21-, I69.31-, I69.81-, I69.91-)
cognitive impairment due to intracranial or head injury (S06.-)
dementia (F01.-, F02.-, F03.-)
mild neurocognitive disorder due to a known physiological condition (F06.7-)
neurologic neglect syndrome (R41.4)
personality change, nonpsychotic (F68.8)
Use additional code
code to identify presence of:
alcohol abuse and dependence (F10.-)
exposure to environmental tobacco smoke (Z77.22)
history of tobacco dependence (Z87.891)
hypertension (I10-I1A)
occupational exposure to environmental tobacco smoke (Z57.31)
tobacco dependence (F17.-)
tobacco use (Z72.0)
Applies from G31 Other degenerative diseases of nervous system, not elsewhere classified
Excludes2 (not included here)
Reye's syndrome (G93.7)
Use additional code
code, if applicable, for codes G31.0-G31.83, G31.85-G31.9, to identify:
dementia with anxiety (F02.84, F02.A4, F02.B4, F02.C4)
dementia with behavioral disturbance (F02.81-, F02.A1-, F02.B1-, F02.C1-)
dementia with mood disturbance (F02.83, F02.A3, F02.B3, F02.C3)
dementia with psychotic disturbance (F02.82, F02.A2, F02.B2, F02.C2)
dementia without behavioral disturbance (F02.80, F02.A0, F02.B0, F02.C0)
mild neurocognitive disorder due to known physiological condition (F06.7-)
MS-DRG index
Defines the logic of DRG(s) 056-057 in MDC 01.
Approximate ICD-9-CM (GEMs)
331.83 Mild cognitive impairment, so stated
Code annotations containing back-references to G31.84
Back-references to G31.84
Type 1 Excludes: F06.7 Mild neurocognitive disorder due to known physiological condition ("mild cognitive impairment due to unknown or unspecified etiology (G31.84)")
Type 1 Excludes: F07.0 Personality change due to known physiological condition ("mild cognitive impairment (G31.84)")
Type 1 Excludes: R41 Other symptoms and signs involving cognitive functions and awareness ("mild cognitive impairment of uncertain or unknown etiology (G31.84)")